Question

X varies directly as y. If x is 9 when y is 4, find x when-y is 8.

Answer 1

Answer:

see explanation

Step-by-step explanation:

Given x varies directly as y then the equation relating them is

x = ky ← k is the constant of variation

To find k use the condition x = 9 when y = 4

k = $\frac{x}{y}$ = $\frac{9}{4}$ = 2.25

x = 2.25y ← equation of variation

When y = 8, then

x = 2.25 × 8 = 18